P0446 Obd Code

[s323al1]

Had to share my 'experience' with this fault on my 2004 Avalanche. After having reset with a OBD code reader numerous times, I finally got frustrated with the repeated error and decided to do full research on this trouble code. Every place including the local Chevy dealership wanted $160 for the evap canister solenoid, plus labor. Only the entire assembly is available from aftermarkets, but no one can get it. Economics, led me to crawl up under the truck and check it out myself. After removing the entire charcoal canister and checking all the vent lines, I found no blockages and reassembled and reset. Lasted about 2 days and CEL pops up agian reading the same code. On next attempt, I pulled just the canister and solenoid off the bracket that attached it to the charcoal canister. Looking closely, I discovered that the solenoid will unscrew from the canister. And upon inspection found that the small spring at the bottom of the solenoind assembly had twisted causing the rubber seal not to seat. Moved this spring back into position. Cleared code..Good to go. This entire assembly is very cheaply made and looks like it would be prone to fail. Solenoid not available separately????? AL

[Indy]

Well done. I've had the code for about 5 years. If we get a warm day I'll check it out.

[pennzoil29]

Welcome aboard, and thanks for the info.

[DofD]

Hi there and welcome to GM Trucks!

 

Thanks for the info, that is good to know.

[gchalifoux]

*** update ***

After further reading I am seeing info about the evap canister mounted ?? somewhere towards the back under the bed of the truck near the fuel tank? so I will be going after that tomorrow to see about removal and cleaning as well as checking the solenoid. more to come....wish me luck!

 

I'm replying to an older post regarding this P0446 code.

 

I have the same code and I need to know what I am looking for. Are there any schematics , links to schematics or pdf documents showing the location of the emissions components under the hood so I can locate this canister to check it out? I'm not affraid to get my hands dirty, but don't want to do any more damage than I have to .

 

Thanks!